Preheat the Oven
Preheat your oven to 425°F (220°C).
Line a large sheet pan with parchment paper or lightly grease it.
Season the Chicken
In a small bowl, combine:
Olive oil
Garlic
Italian seasoning
Smoked paprika
Garlic powder
Onion powder
Salt
Pepper
Rub the mixture evenly over both sides of the chicken.
Prepare the Vegetables
In a large bowl, toss the Brussels sprouts, potatoes, and red onion with:
Olive oil
Garlic powder
Italian seasoning
Salt
Pepper
Spread the vegetables evenly around the edges of the sheet pan.
Place the seasoned chicken in the center.
Roast
Bake for 35–40 minutes, stirring the vegetables halfway through cooking.
The chicken is done when it reaches an internal temperature of 165°F (74°C), and the vegetables are golden and tender.
Serve
Let the chicken rest for 5 minutes before slicing.
Garnish with fresh parsley, a squeeze of lemon juice, or grated Parmesan cheese if desired.